Grain tanks of harvesting machines such as combines and the like are commonly located on the upper regions of the machine. The grain tank will commonly have in it a grain delivery conveyor, usually an auger type, oriented so as to extend upwardly to an outlet through which the grain conveyed by the conveyor is discharged into the tank. To allow utilizing the maximum grain carrying capacity of the tank, it is desirable for the outlet of the conveyor to be positionable at a relatively high elevation in or just above the tank. Additionally, it is now common to employ upwardly extending grain tank extensions around the periphery of the tank to increase its capacity, and as a result, it is desirable for the grain delivery conveyor to be positionable at a sufficient height so as to be capable of filling such higher capacity tanks.
However, a problem that is presented is that the grain delivery conveyor, and in some instances, the grain tank extensions, extend upwardly beyond a maximum height permissible or desirable for the harvesting machine when moving over public thoroughfares and in the vicinity of overhead power and communication lines, and through doorways of equipment storage and repair structures, thus necessitating somehow having the capability for lowering the conveyor and extensions. One known manner for lowering a grain delivery conveyor is to provide a capability along its length for folding. However, such folds have been found to cause grain flow disruptions in operation, which has been found to result in undue wear of components and premature failure. Also, folding does not, in itself, provide a capability for positioning the outlet end of the conveyor at locations between its uppermost operational position, and lower operational positions and a transport position. Additionally, it is a contemplated that as combines grow in size, grain tanks will be taller, longer and wider, so as to require a better capability for distributing the grain therein.
Thus, what is sought is a grain delivery conveyor and drive which can be positioned at various inclinations and positions for delivering grain to a grain tank and for transport and storage, which is not prone to rapid wear and premature failure, and which is adaptable for use with larger grain tanks.